The fan that is commonly used on the factory floor is generally operated by electricity to drive the motor, which in turn causes the fan blades to turn to generate the air current. The operation of such an electrical fan as described above can be adjusted only in a stepped manner and is limited in design in several respects, which are expounded upon explicitly hereinafter.
The conventional electric fan that is used on the factory floor is generally provided with a fan shield of metal material. Such a conventional electric fan can be a fire hazard because the metal shield of the fan can cause a spark at the time when the fan is accidentally thrown off balance to fall on the factory floor. Therefore, it is not safe to operate such electric fans in many areas, such as a natural gas factory, a chemical factory, a storage depot of paints containing the volatile chemical substances like toluene and acetone, an iron melting works, a humid basement, etc.
The conventional electric fan is not cost effective in view of the fact that it is not energy efficient. In addition, the application of the fan is limited in that it rotates unidirectionally and that it generates the air current in a stepped manner.
The conventional electric fan is often moved around on the factory floor, thereby causing the damage to the surface of the factory floor and to the electric cord attached to the fan. The structural damage of the electric cord can often bring about the leakage of electricity.